1. Field of the Invention
The present invention relates to an individual sheet member output control method used in a sheet member dispenser and more particularly, to such an individual sheet member output control method, which return dispensing sheet members that are detected overlapped and dispense the returned sheet members again, preventing shutdown of the machine due to a false judgment.
2. Description of the Related Art
Following fast development of technology, our mode of living has been changed. Various automatic vending machines (ticket venders, coin exchanging machines, etc.) are used everywhere to sell different products without serviceman. These automatic vending machines save much labor and bring convenience to people. An automatic vending machine may be quipped with a sheet member dispenser to dispense sheet members (cards, tickets, coupons, banknotes, etc.). However, due to thin thickness of sheet members, two or more sheet members may be overlapped or stacked when they are delivered toward the sheet member outlet. Manufacturers are trying hard to design sheet member dispensers that can dispense sheet members smoothly and individually.
FIG. 11 is a schematic side view of a sheet member dispenser according to the prior art. As illustrated, the sheet member dispenser A comprises an accommodation chamber A1, a gap adjustment device B disposed at the front side of the accommodation chamber A1, a plurality of sheet transferring rollers A2 disposed beneath the accommodation chamber A1, a motor A3 controlled to rotate the sheet transferring rollers A2 and to transfer sheet members (for example, banknotes) C out of the accommodation chamber A1 to the sheet member path defined by the gap adjustment device B. According to this design, the circumferential length of the sheet transferring rollers A2 is shorter than the length of the sheet members C, and the sheet transferring rollers A2 are molded from a material having a high friction force, for example, rubber. Therefore, the transferring rollers A2 keep transferring sheet members C forwards when rotated. To control dispensing of one single sheet member C at a time, the ratio between the circumferential length of the transferring rollers A2 and the length of the sheet members C must be measured and then transferring rollers A2 are rotated through an angle corresponding to the length of one single sheet member C. However, this limitation does not allow the sheet member dispenser to dispense different sizes of sheet members. Further, the transferring roller A2 transfer sheet members C by means of a friction force. However, sheet members C may be adhered together due to the effect of static electricity, water content, burrs, or ink. Further, due to precision reason, the gap adjustment device B may be not able to adjust the gap of the sheet member path to fit the thickness of one single sheet member C perfectly. In this case, two overlapped or stacked sheet members C may be dispensed. If the gap of the sheet member path adjustment device B allows only one single sheet member C to pass, a second sheet member C may be jammed in the gap adjustment device B or in between the gap adjustment device B and the accommodation chamber A1 when a first sheet member C of two overlapped sheet members C is moved through the sheet member path, resulting in damage of the sheet member dispenser A.
Therefore, it is desirable to provide an individual sheet member output control method for sheet member dispenser that eliminates the aforesaid problems.